Fluid-pressure plunger.



No. 846,685. PATENTED MAR. 12, 1907.

E. H. MUMFORD.

FLUID PRESSURE PLUNGER. APPLICATION FILED Nov. 9, 1905.

2 SHEETS-SHEET 1.

INVENTOR PATENTED MAR. 12, 1907.

H. MUMFORD.

FLUID PRESSURE PLUNGER.

APPLICATION FILED NOV-9,1905.

g) I ZIIEETSSHEET 2.

INVEN'I'OR EDGAR H. MuivrFoRn, or

NEWTOWN TOWNSHIP, DELAWARE COUNTY,

PENNSYLVANIA.

FLUID-PRES SURE PLUNGER.

Specification of Letters Patent. Atnlication filed November 9, l flfif 'flerial No. 286,522.

Patented March 12, 1 907.

' To all whom, it may concern:

Be it known that 1; EDGAR'H. Mamet, a

, citizen of the United-States, residingat Newspecification.

town township, in the county of Delaware and State of Pennsylvaniahave invented certain new -and useful Improvements in F hid-Pressure Plungers, of which the following 1s a .This invention has reference to" an improved construction of fluid pressure plunger used for exerting pressure, as for example in connection with molding machinery in which connection it issho wn, 1n the accompanying drawings, whereinf Figure lshows: a side elevation of a moldmg machine with imy improved form of plunger applied on each side thereof;

Figure 2 is a sectional view on a vertical plane; 3

Figure 3 is aztransverse section on the line (3) (3) of Figure 2 Figure 4 is a'transverse section on the line (4) (4 of Figure 2, and

Figure 5 is, a bottom plan view of the plunger casing] The primary; object of this resent inventi on is to. construct a device 0 the character specified in whicha liquidas for example oil or waterfi's used to impart motion and pressure to the'plunger or ram and is permitted to act on the lower end thereof, while on the upper surface of such liquid a fluid of a lighter characteryasi for example air, is allowed to actfand form a separating medium between the liquid and the stufling box or packing for theplunger or ram. In order to aflord a meansifor allowing the liquid 'to flow back and forth to compensate for movement of the ram and to fix a level above which it shall not rise,Qa-'storage chamber is formed in the interior casing, to the upper side whereof the gaseous fluid or air is admitted.

In order to betterunde'rst'and the nature of my present invention, 1 wilhexplain the same in detail in connection with: the accompany ing drawings, and particularly, Figure 2 thereof in which, as will appearffrom examination of the same,.there is a lu'nger or ram casing 6 containing a ram 7 a apt'edto move vertically and havinga space 8 at, .the lower end thereof and a passage 9 through which the liquid may reach said space, theamount of. opening of said passage when the ram is in i the lowermost position being capable of adjustment by means of the valve 10 carried on the adjustable stem 11.

About midway of the length of the casing 6 there is a chamber ,12 which I call an overflow or storage chamber which communicates with the lower end of the casing by means of the passage 9, and is of sufficient capacity to accommodate all ofthe liquid used in the operation of the ram. Into the-upper end of the casing. 6 there is an inlet opening 13 through which air or'other fluid of like character under pressure is introduced in order to exert a pressure downward upon the. liquid in the lower portion df the casing, and at 15 another openingfor the admission of oil or other liquid.

At the extreme upper end of the casing there is a packing 14 contained within astufiingbox of ordinary construction and adaptto prevent leakage of the fluid around the ram or plunger.

The device as shown in the drawings is adapted for attachment to a molding machine in the position indicated sin Figure 1, there being in such construction one of the casings, 6, attached to the frame 17 of the 0 machine on either side thereof, and arranged to raise and lower the table 16 above.

It will be readily seen that in the construction above described the pipe connection leading to the passage 13 contains at all 5 times onlythe lighter fluid, the liquid itself not having to pass into or out of the casing,

. but only rising as the plunger descends, and

occupying the storage recess 12 provided for that purpose. lighter fluid or air on the upper side of the liquid also serves to separate the liquid from the packing 14, and keeps the device tight against leakage of the fluid, since it is prac',

tically impossible to prevent some leakageos past plunger packing in contact with a liquld and by keeping up the supply of pressure fluid, as air next-the packing, any leakage of pressure liquid, as oil, is prevented, and the supply of pressure fluid, as'air, is always abundant and its leakage innocuous, whereas the supply of liquid, as oil, is limited and its leakage very troublesome.

Anotheradvantage of this improvement is that the air-in the supply passage'also facili- The introduction of the '90 Q5 tates the operation of the device, since air IQ for, said casing moves. with muchless friction than a liquid l above the "lower-end, and a paekingvabove would, which is most essential in securing the said storage chamber, with means for introsynchronous action of the plungers. 4

Having thus described my invention and 5 illustrated its use, what I claim as new, and

desire to secure by Letters Patent, is the fol- I In testimony whereof I have hereunto lowing: signed my name in the presence of the two A plunger apparatus comprising in corn- 5 subscribed witnesses.

binatlon, a rain, a casing or chamber there- EDGAR H. MUMFORD.,

being constructed to stand f Witnesses:

in vertical position with a liquid chaniber I} A. E. SWEETMAN at the lower'end, and a storage chamber 1 CI-IAs. H. THUMLERT.

packing andsaid storage chamber, substantially as described.

ducinga lighter fluid, as air, between said I 

